Melanoma

Melanoma

 

Melanoma is a malignancy of the melanocytes; this disease is experiencing a rising incidence and mortality worldwide.

Epidemiology

  • Incidence – 18/100,000
    • Tripled over the last 20 years
    • Highest incidence worldwide is in Australia
  • Age – median is 57 years; rare in children
  • Sex – M:F;1.5:1
  • Ethnic – tenfold increase in incidence in Caucasians

Risk Factors

  • Sunlight – sunburns in childhood, intermittent UV exposure associated with higher risk
  • Blue or green eyes; red or blond hair
  • Melanocytic nevus – increased risk by number and size of nevi
  • Family history – twofold risk if first-degree relative had melanoma
    • Clustering of melanoma in familial retinoblastoma, Lynch type II, Li-Fraumeni syndrome
    • Increased risk if family history of pancreatic cancer or astrocytoma exists
  • Immunosuppression

Clinical Presentation

  • Nevus with asymmetry, border irregularity, color variation, diameter >6 mm and evolving changes (ABCDE guideline)
  • Ulceration, pigment loss
  • Types – superficial spreading, nodular, lentigo maligna, acral lentiginous
    • Superficial spreading is most common
  • Rare sites – eye (iris, ciliochoroidal), mucosal

Diagnosis

  • Pathology
    • Histologic appearance is diagnostic
  • Laboratory testing
    • S-100B, serum
      • Used for determining prognosis
      • Rising concentrations indicate disease progression

Prevention

  • Decrease sun exposure
  • Sunscreen